Preparation of Ag-deposited porous TiO2 films using polystyrene nanoparticles as templates for enhanced photocatalysts

Titanium dioxide (TiO2) is used as a photocatalyst in such processes as industrial wastewater treatment since it is a large-band-gap semiconductor with a catalytically active surface. For improvement of photocatalytic activity, many developments of TiO2 have been studied with physical and chemical modifications. In this study, the monodisperse polystyrene colloid was prepared via emulsion polymerization, then the porous TiO2 inverse opal (TIO) film was manufactured through dip coating process using polystyrene (PS) as templates. The inverse opal structure has a large surface area and it makes to improve the phtocatalytic performance of TiO2. After that, a small amount of silver nanoparticles were deposited on the surface of TIO films through photodeposition method to inhibit charge carrier recombination and increase the photocatalytic activity. This silver-deposited TIO film can be used as an enhanced photocatalyst. The resultant samples were characterized by TEM, DLS, FE-SEM, XPS, EDS, and UV-Vis spectroscopy. Furthermore, photocatalytic performance was analyzed by photodegradation of methylene blue dye in aqueous solutions.